Effects of testosterone on circadian rhythmicity in old mice

The journal of physiological sciences

article

Atsuyoshi Hashimoto¹  Shingo Fujiki¹  Wataru Nakamura²  Takahiro J. Nakamura¹ 

[1] Laboratory of Animal Physiology, School of Agriculture, Meiji University;Department of Oral-Chrono Physiology, Graduate School of Biomedical Sciences, Nagasaki University

关键词: Circadian rhythm;    Testosterone;    Wheel running;    Free-running period;    PER2LUC;   

DOI  :  10.1007/s12576-019-00695-4

来源: Springer

【 摘 要 】

Serum testosterone concentration decreases with age in humans and rodents. Accordingly, old male mice show changes in locomotor activity rhythms: a lengthened free-running period and decreased activity levels among others. To investigate whether testosterone replacement improves the age-related decline in circadian rhythmicity, we examined the effects of testosterone on the circadian rhythms of wheel running activity in old male mice. Intact male C57BL/6J mice (18–22 months old) were subcutaneously implanted with silicone tubes packed with testosterone propionate (TP) or cholesterol. TP treatment significantly decreased the daily wheel running revolutions in a normal light/dark (LD) cycle and in constant darkness (DD), but did not affect the free-running period. The same experiment performed on young male gonadectomized mice (3–5 months old) demonstrated that TP treatment significantly increased activity levels in both LD and DD. These results suggest that testosterone replacement exacerbates the age-related decline in circadian rhythmicity.

【 授权许可】

Unknown